As temperatures drop and snow starts to fall, bears make their way into a deep sleep to survive the winter. Despite what many assume, this state is called torpor, not true ‘hibernation.’

Here are some of the key differences between hibernation and torpor:

Physiological changes

According to the National Forest Foundation (NFF), torpor is a survival tactic that animals use to survive the winter and involves decreased breathing and heart rates, a lower metabolic rate, and a slightly reduced body temperature.

Wakefulness

The NFF says that the major difference between hibernation and torpor is that the animal can wake up quickly to avoid danger and even leave their den to eat.

The NFF also says waking up during torpor expends a lot of energy, and even involves violent shaking and muscle contractions like shivering. However, that lost energy is offset by energy saved in the torpid state.

Voluntary/Involuntary

Torpor is involuntary, unlike hibernation. It lasts for shorter periods of time, and animals in torpor have a normal body temperature, breathing, and heart rate during their active part of the day.

Learn more about bears and torpor here.

STAY INFORMED: Get free Colorado news with our daily newsletter (Click here)